Does White Noise Help You Learn?

Most people have trouble focusing when there are distractions, and that will surely impair learning. Learning can be impaired by distracting background sounds. That is why teachers generally encourage students to study in quiet environments. Children, however, like extra stimulation when studying, perhaps because they view study as boring. So, a common practice is to play music or even have the radio or TV on. I have written about music effects on learning before (http://thankyoubrain.blogspot.com/search?q=music), but now there is other information I would like to share.

Personality of the learner may be an important variable. Adrian Furnham and Lisa Strbac of University College, London, found that both background music or office noises impaired performance of introverts in tasks involving reading comprehension, mental arithmetic, and prose recall. Performance in silence was the same for both personality types, suggesting that introverts have a special need for silence in their study environments.

The notion has surfaced that it might be beneficial to mask distracting sounds by playing white noise while studying. White noise is a random mixture of sound frequencies that when heard in low volume can improve detection of a simultaneous isolated signal with equal power of any frequency. Perhaps this is because the presence of a homogenous signal (white noise) improves the contrast with a novel superimposed signal. A contributing factor might be the brain’s usual response of habituating to a constant stimulus, effectively creating an empty-stimulus state in which other stimuli would be augmented. A couple of years ago a study was reported indicating that a white-noise background can improve memory in youngsters with Attention Deficit Disorder.

What happens in a brain exposed to white noise has been revealed in fMRI brain-scan studies of young adults. The study’s behavioral test indicated slightly improved recognition memory of scene images and scans. An associated increased activity occurred in brain positive reinforcement pathways and in auditory cortex.

However, some caution is needed in interpreting these results. One caveat is that the study of adults used recognition memory (as in “Do you remember seeing this scene?”), which is much less robust than being able to generate a recall without cuing. Another caveat is the lack of systematic evaluation of the decibel level of white noise. At some point, the sound is certain to be distracting or even irritating. In fact, people on average report that such noise is slightly aversive and strongly aversive by some subjects. The adult study used a white noise of 20-5000 Hz at 70 dB via headphones. If one does not deliver white noise via headphones, other sounds in the room could negate whatever beneficial effect white noise might have.

Steven Smith at my university found that recall of memorized words was better 48 hours after learning if the sounds used during word presentation, either music or white noise, were repeated during the recall session. This reflects a common observation that recall is enhanced if you are tested in the same environment as when you learned the test material. Using sound in this way is not practical in school situations, but it could improve the efficacy of self-testing in one's home environment.

We should not accept uncritically the studies that advocate white-noise backgrounds during learning. One study revealed that exposure to background noise improved performance for inattentive children but worsened performance for attentive children. Thus, white noise may be a distraction for attentive children and only helps with inattentive children because their innate distractibility is activated less when the noise background is monotonous and uninteresting.

In the most recent study of this issue, white-noise (20-20,000 Hz, 70 dB, via headphones) during initial learning impaired recall. The authors concluded that white noise has no general beneficial effect on thinking and memory.

What this tells me is that white noise might have some value if there is general room noise that needs to be masked. This might be especially true for people with attention deficits who are especially distracted by noise. Another possibility, which as far as I know has not been tested, is to have a soft background noise of rain in a tropical rain forest or waves lapping on the beach. Those sounds would surely be relaxing and provide a uniform sound background.

But why have any sound at all? What is wrong with utter silence when you are trying to concentrate? When it comes to learning, it is hard to beat the silence of the library.

Furnham, Adran, and Strbac, Lisa. (2010). Music is as distracting as noise: the differential distraction of background music and noise on the cognitive test performance of introverts and extraverts. Ergonomics, 45(3). http://dx.doi.org/10.1080/00140130210121932